Furnace heat circulator



Sept. 6, 1932. c. E. PEARSON ET AL 1,875,393

FURNACE HEAT CIRCULATOR "Filed April 17, 1950 2 Sheets-Sheet 1 1 N V EN TORJ! A TTORNE Y.

p 6, 1932- c. E. PEARSON ET AL 1,875,393

FURNACE HEAT CIRCULATOR Filed April 17, 1950 2. Sheets-Sheet 2 INVENTORJ.

Haw/ Mu A TTORNE Y.

Patented Sept. 6, 1932 UNITEDSTATES} PATENT] OFFICE ormnnns nrnmson AND ERVY I- DAVIS, on ST. PAUL, MINNESOTA runNAoE HEAT GIRCULATOR Application filed. April 17,

the purpose stated. 1

In the accompanying drawings,''-

Fig. 1 is a slightly perspective, rear elevation of a warm air furnace and ourimproved device in operative position. I

Fig. 2 is asectional elevation in horizontal plane through the lower part of the furnace, about as on line 22 inFig. 1.

Fig. 3 is an enlarged detail VLQW of the lower, rear part of the furnace partly in section, and a left hand exterior View of our device, about as on line 33 in Fig. l and looking toward the right from said line. h

Fig. 4 is an approximately central, sectional elevation, in enlarged scale, of the lower part of the furnace and through our device about as on a vertical plane at line H in Fig. 2.

Fig. 5 is a modification of Fig. 2 showing a centrifugal type of fan.

Referring to the drawings by reference numerals, 5 designates the usual upright cylin drical type furnace for hot-air heating, said furnace surrounded concentrically by the shell 6. 7 designates the usual ash pit and its outlet through shell- 6 normally closed by door 8 (see Fig. 2).

9 are the cool-air return pipes, shown as communicating with extended lower parts 6A of shell 6. In present type of furnaces the cool air thus returning is drawn upwardly between shell 6 and furnace 5 being heated as it rises and circulates through fines connected as at SF (Fig. 1) or other means, not shown,

to the rooms of a house.

10 in Fig. 1 designates the furnace smoke flue. The natural circulation and heating of the moving air is common to practically all warm-air furnaces, but various means have been devised to accelerate the warm air. Our device provldes a simple and efi'ective means 1930... Serial No. 445,064.

for this purpose as will now be described. The device is of such construction as to require no added fiues or changes in the furwalls 12A extending outwardly from thefurnace and said sidewalls connected by a continuous sheet 12B, said parts at the outer end of the shell being rounded in'the form of a half-drum. Concentric of said latter part is journaled a fan shaft 13 in the side walls, the shaft being extended exteriorly from one wall and carrying a driven belt pulley 14. 15 is an electric-motor having a drive pulley 16 on its spindle 16S alined with pulley l4 and connected therewith by a'belt 17. 18 is a multi-blade propeller of paddlewheel type, fixed on shaft 13.

19 is a partition member extending from the fan toward the end of housing 12 opening into the shell 6, said partition fixed to the side walls 12A and dividing the said mouth part of the shell 12 into an upper and a lower air passage, designated A and B respectively. When the fan is set in motion in proper direction, its action causes all'the air at the base of the furnace to be drawn through passage B and bedelivered with predetermined velocity through passage A, the latter current of air being directed upwardly and around the furnace, within shell 6. The upward direction of this air is facilitated by the inwardly and upwardly inclined fins or exten sions 'and 19C of members 12 and 19' respectively (see Fig. 4;).

Obviously the air returning to the furnace in ducts 9 is drawn into the fan housing at the lower level as indicated by the arrows 20 and the means just described cause a forced upward circulation designated by arrows 21, the latter currents of air being heated by the furnace and being kept in forced circula-' tion continuously by the fan.-

The proportions of drive pulley 16 and driven pulley 14 must be governed by the motor speed and the required R. P. M.s of. the fan'for proper forced circulation. Obvi-' ously the belt 17 is only shown as one form of drive, other means such as gear drive being perhaps desired in some cases. We have shown the motor mounted on a block 22 which is fixed to the floor 11.

In Figs. 1 and 2, 23 are upright, short supports of sheet iron or other suitable material, forming guards inwardly of the lower outlet of ducts 9, and both within the housings 6A, to prevent air from circulating directly upward after beingdischa'rged from Thus such air is directed toward 7 r planewlthth'e shaft of the fan and dividing said ducts. the fan housing.

In Fig. 5 a centrifugal type of fan. 18is shown and occupies approximately one half of the space in the housing. With this type of fan the cool "air is drawn through passage Bias before, then sucked into the Central part of the fan as indicated by arrows 20A and blown out through passage A (as arrows 21A). This passage A is formed between a vertical partition 19? and a wall 12A to lead airdirectly toward the furnace but 05 center of the furnace so that the air current is started upwardly and around the furnace in a spiral action indicated by the arrows 21A.

Thepositive mechanical forced circulation of the air inthe heating system provides for rapid circulation and an even temperature in all rooms heated by a furnace with means air outlet means in the upper part of'saidi furnace, return-air intake means comprising pipes communicating with the lower interior of said shell; sa1d 0 u 7 v i I prising ran housing mounted exterlorly of and fixed to the lower part of saidshell and j communicating wi h the interior thereof through an aperture provided therein,v a

radial winged fan mounted in the outermost part of said houslngon a horizontal shaft journaled therein, said fan arranged to be rota-ted in a direction to draw air thru its housing from the lower part of said shell and to expel air from said housing into thespace between the heated drum and said: shell atan;

elevationa'bove the said air intake: action of the fan; a horizontal partitionfixed in: said fan housing between the fan and the; furnace shell comprising a plate dividing that part of the-fan housing into a lower and anupper' 2. An air circulatingqdevice for hot a'i r" furnaces having an outer shell and an innerheatmg drum concentr c thereof forgenerat circulating device coming warm air between it and the said shell, air return pipes connected with the lower interior part of the shell, warm air outlet means in the upper part of said shell for suitable heat distribution means; said circulating device comprising a horizontally elongated housing. withtone end fixed to said shell. and opening. thereintoat its lower part, said housing extending outwardly from the shell, a blower fan rotatably mounted in the outer end part ofsaid housing, ahorizontal partit on within the houslng in a common therhousing intoanupper and a lower duct between said fan and the shell, said fan expel Said air through said upper "duct into the shell and around said heating drum in an upward direction from the outlet end of said upper duct, means for directing said latter airv current in an upward'direction compris-' ing upwardly inclined extension plates bet vecn said shell and heating drumand comprising integral parts of said upper duct.

3. In a warm air circulating device for furnaces havingv a centralheating. drum, a shell surrounding said drum concentrically, hot air e -itl-etmeans in the upper part of said furnace, return-air intake means comprising pipes communicating withthe lower interior of said shell ;I said circulating device comprising aifanhousing mounted exteriorly of and fixed tothe lower part of said shell and communicating with the; interior thereof through an'aperture provided therein, a radially winged. fan mountedwin the outermost part of saidhousing ona horizontal shaftjournaled therein, and a horizontal partition insai'dfanvihousing between the fan and the aperture of said housing, comprising plate means dividing saidpart of the-fan heusing into a lower air i-ntake passage and an upper air outletpassagef v V ,In'testimony whereof we a'ifix our signatures. or 1 7' CHARLES PEAR-SON.

' ERVY L-DAVIS; I 

